1. Field of the Invention
The present invention relates to a shift lever device having a shock absorbing structure.
2. Description of the Related Art
As shown in FIG. 25, a lower end of a shift lever 202 is mounted on a control shaft 204 and the control shaft 204 is axially supported by a shaft 208 whose both ends are supported by bearings 206. As a result, when a shift operation of the shift lever 202 is effected, the control shaft 204 rotates to allow selection of a desired shift range.
However, when a strong force is applied to the shift lever 202 in the axial direction, the shift lever 202 does not have sufficient absorbing ability to the force.
In view of the above-described circumstances, it is an object of the present invention to provide a shift lever device having an improved absorbing ability to a strong force acting in the axial direction.
A first aspect of the present invention comprises a shift lever which allows selection of an arbitrary shift range by shift operation, and supporting means which rotatably supports the shift lever outside an interior of a vehicle, wherein when axial impact force is applied to the shift lever, the supporting means is broken.
In the shift lever device according to the first aspect, usually, the shift lever is supported rotatably by the supporting means and an arbitrary shift range can be selected by shift operation.
When impact force (strong force) is applied to the shift lever in the axial direction, the supporting means is broken. Due to the breakage of the supporting means, the impact force applied to the shift lever can be absorbed. Namely, in the shift lever device of the present invention, since the impact force applied to the shift lever can be absorbed by breakage of the supporting means. For this reason, as compared with a conventional shift lever device, the absorbing ability to the impact force is improved.
A second aspect of the present invention is constructed such that, in the first aspect, the supporting means includes: a control shaft to which a lower end of the shift lever is connected so as to allow the shift lever to be rotatable in a longitudinal direction of the vehicle; a bearing portion in which a shaft supporting hole by which the control shaft is supported is formed; and a thin-walled portion formed between the shaft supporting hole and an escape hole formed in the bearing portion.
In the shift lever device according to the second aspect, usually, the control shaft is supported by the shaft supporting hole of the bearing portion, and therefore, the shift lever is operated to rotate the control shaft and an arbitrary shift range can be selected.
When impact force is applied to the shift lever in the axial direction, the thin-walled portion of the bearing portion is pressed by the control shaft and is thereby broken. Due to the breakage of the thin-walled portion, the impact force applied to the shift lever can be absorbed. After the thin-walled portion is broken, the control shaft comes into the escape hole and moves in the direction in which the impact force acts.
As described above, the thin-walled portion is provided between the shaft supporting hole and the escape hole formed in the bearing portion, and therefore, the impact force applied to the shift lever can be absorbed without increase in the number of parts.
A third aspect of the present invention is constructed such that, in the second aspect, the transverse dimension of an opening of a hole wall forming the escape hole is made smaller than the diameter of the control shaft and is gradually made smaller in the direction away from the shaft supporting hole.
In the shift lever device according to the third aspect, after the control shaft breaks the thin-walled portion and comes into the escape hole, the control shaft abuts against the hall wall of the escape hole and moves while widening the escape hole in the transverse direction. For this reason, the decay time of impact force becomes longer and the impact force can be effectively absorbed.
A fourth aspect of the present invention is constructed such that, in the first aspect, a fragile portion is formed in a breaking portion of the supporting means which is broken due to axial impact force applied to the shift lever so as to partially lower strength of the breaking portion.
In the shift lever device according to the fourth aspect, when impact force is applied to the shift lever in the axial direction, first, breakage is caused in the fragile portion, and subsequently, the supporting means is broken. With the breakage being caused in the fragile portion as described above, the impact force can be effectively absorbed.
A fifth aspect of the present invention is constructed such that, in the first aspect, a fragile portion is formed in a breaking portion of the supporting means which is broken due to axial impact force applied to the shift lever so as to partially lower strength of the breaking portion, and at least one pair of wall surfaces is formed further at the front side than the breaking portion in a direction in which the impact force acts so that the space therebetween is gradually made smaller in a direction away from the shaft supporting hole.
In the shift lever device according to the fifth aspect, when impact force is applied to the shift lever in the axial direction, first, breakage is caused in the fragile portion, and subsequently, the thin-walled portion is broken. With the breakage being caused in the fragile portion as described above, the impact force can be effectively absorbed. Further, after breaking the thin-walled portion, the control shaft abuts against the wall surfaces and moves while widening the space of the wall surfaces in the transverse direction. For this reason, the decay time of impact force becomes longer and the impact force can be effectively absorbed.
A sixth aspect of the present invention is constructed such that, in the first aspect, the supporting means includes: a control shaft supported by a bearing portion of a shift lever device main body; a bracket mounted on the control shaft; a pin which is inserted in and passes through a through hole formed in the bracket and an axial hole formed in the shift lever so as to support the shift lever in a rotatable manner; a thin-walled portion formed in the bracket, wherein when axial impact force is applied to the shift lever, the thin-walled portion is broken; and a breaking portion formed in the pin at the side of the thin-walled portion and provided to be broken due to axial impact force being applied to the shift lever.
In the shift lever device according to the sixth aspect, usually, the shift lever is rotatably supported on the bracket by the pin. When the shift lever is operated to rotate the control shaft, an arbitrary shift range can be selected.
When impact force is applied to the shift lever in the axial direction, the thin-walled portion is pressed and broken by the shift lever and the breaking portion of the pin is also broken. Due to this breakage, the shift lever and a portion of the bracket are removed from the control shaft together with the pin and moves in the direction in which the impact force acts, thereby resulting in absorption of the impact force.
As described above, by providing a simple structure in which the thin-walled portion is formed in the bracket and the breaking portion is formed in the pin, the impact force applied to the shift lever can be absorbed.
A seventh aspect of the present invention is constructed such that, in the sixth aspect, the bracket includes a rotating bracket which rotates together with the control shaft, and a supporting bracket which projects from the rotating bracket and supports the control shaft, wherein the thin-walled portion is formed in the supporting bracket at a position where the supporting bracket is connected to the rotating bracket.
In the shift lever device according to the seventh aspect, the thin-walled portion is formed in the supporting bracket at the location where the supporting bracket is connected to the rotating bracket. Due to the impact force applied to the shift lever, bending moment acts on the location where the supporting bracket is connected to the rotating bracket, and the thin-walled portion is thereby broken.
An eighth aspect of the present invention is constructed such that, in the sixth aspect, the breaking portion is formed by making a hole in the pin along an axial direction of the pin.
In the shift lever device according to the eighth aspect, the breaking portion can be formed in the pin without alteration of the appearance of the pin, no alteration in the shape of a mounting portion of the pin is required.
A ninth aspect of the present invention is constructed such that, in the sixth aspect, the bracket includes a rotating bracket which rotates together with the control shaft, and a supporting bracket which projects from the rotating bracket and supports the control shaft, wherein the thin-walled portion is formed in the supporting bracket at a position where the supporting bracket is connected to the rotating bracket, and the breaking portion is formed by making a hole in the pin along an axial direction of the pin.
In the shift lever device according to the ninth aspect, the thin-walled portion is formed in the supporting bracket at the location where the supporting bracket is connected to the rotating bracket. Due to the impact force applied to the shift lever, bending moment acts on the location where the supporting bracket is connected to the rotating bracket and the thin-walled portion is thereby broken. The breaking portion can be formed without alteration of the appearance of the pin, no alteration in the shape of a mounting portion of the pin is required.
A tenth aspect of the present invention is constructed such that, in the first aspect, the supporting means includes: a control shaft supported by a bearing portion of a shift lever device main body; a bracket mounted on the control shaft; and a pin which is inserted in and passes through a through hole formed in the bracket and an axial hole formed in the shift lever so as to support the shift lever in a rotatable manner, the pin being pressed and broken by the shift lever when axial impact force is applied to the shift lever.
In the shift lever device according to the tenth aspect, usually, the shift lever is rotatably supported on the bracket by the pin. When the shift lever is operated to rotate the control shaft, an arbitrary shift range can be selected.
When impact force is applied to the shift lever in the axial direction, the pin is pressed and broken by the shift lever and the shift lever is removed from the bracket together with the pin and moves in the direction in which the impact force acts, thereby resulting in absorption of the impact force.
As described above, by providing a simple structure in which the shift lever is rotatably supported on the bracket by the pin which is pressed and broken by the shift lever due to the axial impact force applied to the shift lever, the impact force applied to the shift lever can be absorbed.
An eleventh aspect of the present invention is constructed such that, in the first aspect, the supporting means includes: a control shaft to which a lower end of the shift lever is connected so as to allow the shift lever to be rotatable in a longitudinal direction of the vehicle; a bearing portion in which a shaft supporting hole by which the control shaft is supported is formed; and a diameter-reduced portion formed in the control shaft and provided to be pressed and broken by the shift lever device due to axial impact force being applied to the shift lever.
In the shift lever device according to the eleventh aspect, usually, the control shaft is supported by the shaft supporting hole of the bearing portion. For this reason, when the shift lever is operated to rotate the control shaft, an arbitrary shift range can be selected.
When impact force is applied to the shift lever in the axial direction, the control shaft is pressed by the shift lever and the diameter-reduced portion is broken. Due to this breakage, the shift lever and the control shaft are separated from the bearing portion and move in the direction in which the impact force acts, thereby resulting in absorption of the impact force.
As described above, the impact force applied to the shift lever device is absorbed due to the breakage of the diameter-reduced portion formed in the control shaft, and therefore, the structure of the device becomes simple without increase in the number of parts.
A twelfth aspect of the present invention is constructed such that, in the eleventh aspect, a hollow portion is formed in the control shaft along an axial direction of the control shaft.
In the shift lever device according to the twelfth aspect, the control shaft is lightened by forming the hollow portion therein. By changing the shape of the hollow portion in the axial direction of the control shaft, the breaking strength of the diameter-reduced portion can be varied.
A thirteenth aspect of the present invention is constructed such that, in the eleventh aspect, a plurality of diameter-reduced portions is provided at different positions along the axial direction of the control shaft and at least one of the plurality of diameter-reduced portions has a different breaking strength than those of other diameter-reduced portions.
In the shift lever device according to the thirteenth aspect, the difference in time of breakage is caused between the diameter-reduced portions, and therefore, the impact force applied to the shift lever can be effectively absorbed.
A fourteenth aspect of the present invention is constructed such that, in the first aspect, the supporting means includes: a control shaft to which a lower end of the shift lever is connected so as to allow the shift lever to be rotatable in a longitudinal direction of the vehicle; a connecting plate on which a shaft supporting hole by which the control shaft is supported is formed; and a shear plate which is inserted in and passes through a supporting hole formed in the connecting plate and a fixed hole formed in a main body frame of the shift lever device so as to allow the connecting plate to be fixed to the main body frame, the shear plate being pressed and broken by the connecting plate when axial impact force is applied to the shift lever.
In the shift lever device according to the fourteenth aspect, usually, the control shaft is supported by the shaft supporting hole of the connecting plate and the connecting plate is fixed to the main body plate by the shear plate. For this reason, when the shift lever is operated to rotate the control shaft, an arbitrary shift range can be selected.
When impact force is applied to the shift lever in the axial direction, the connecting plate by which the control shaft is supported is provided to move in the direction in which the impact force acts. As a result, the shear plate is pressed and broken by the connecting plate, and therefore, the connecting plate is separated from the main body frame and moves in the direction in which the impact force acts, thereby resulting in absorption of the impact force.
Further, the shift lever and the connecting plate can be disposed on a straight line, and therefore, no space for installation is required.
A fifteenth aspect of the present invention is constructed such that, in the fourteenth aspect, the shear plate is formed of a material whose strength is lower than those of the connecting plate and the main body frame of the shift lever device.
In the shift lever device according to the fifteenth aspect, only the shear plate is broken without breaking the connecting plate and the main body frame so that the impact force applied to the shift lever can be absorbed.
A sixteenth aspect of the present invention is constructed such that, in the first aspect, the supporting means includes: a control shaft supported by a bearing portion of a shift lever device main body and having an insertion through hole formed therein; a bracket provided in a lower portion of the shift lever and having a shaft supporting hole formed therein; a pin which is inserted in and passes through the through hole and the supporting hole; and a thin-walled portion formed between the shaft supporting hole and an escape hole formed in the bracket.
In the shift lever device according to the sixteenth aspect, usually, the pin is inserted in and passes through the shaft supporting hole of the bracket and the insertion through hole of the control shaft. When the shift lever is operated to rotate the control shaft, an arbitrary shift range can be selected.
When impact force is applied to the shift lever in the axial direction, the bracket formed at the lower end of the shift lever is pushed against the pin, and therefore, the thin-walled portion of the bracket is pressed due to this reaction and is thereby broken. Due to the breakage of the thin-walled portion, the pin moves in such a manner as to come into the escape hole, and therefore, the impact force applied to the shift lever can be absorbed.
As described above, the thin-walled portion is provided between the shaft supporting hole and the escape hole formed in the bracket of the shift lever, and therefore, the impact force applied to the shift lever can be absorbed without increase in the number of parts.
A seventeenth aspect of the present invention is constructed such that, in the sixteenth aspect, the transverse dimension of an opening of a hole wall forming the escape hole is made smaller than the diameter of the pin and is gradually made smaller in the direction away from the shaft supporting hole.
In the shift lever device according to the seventeenth aspect, after the pin breaks the thin-walled portion and comes into the escape hole, the pin abuts against the hole wall of the escape hole and moves while widening the escape hole in the transverse direction. For this reason, the decay time of impact force becomes longer and the impact force can be effectively absorbed.
An eighteenth aspect of the present invention is constructed such that, in the first aspect, the supporting means includes: a spherical body to which a lower end of the shift lever is connected; a spherical body receiver which holds the spherical body; a receiving pedestal which supports the spherical body receiver in a rotatable manner; and a bearing portion by which the receiving pedestal is mounted to the shift lever device main body and which is broken due to impact force applied to the shift lever.
In the shift lever device according to the eighteenth aspect, usually, the spherical body receiver for holding the spherical body is supported on the receiving pedestal in a rotatable manner and the receiving pedestal is mounted to the main body by the bearing portion. For this reason, when the shift lever is operated to rotate the spherical body, an arbitrary shift range can be selected.
When impact force is applied to the shift lever in the axial direction, the spherical body presses the spherical body receiver. As a result, the receiving pedestal is also pressed and the bearing portion is broken, the spherical body receiver is separated from the shift lever device main body, and further, the shift lever moves in the direction in which the impact force acts, thereby resulting in absorption of the impact force.
As described above, the impact force acts on the bearing portion via the spherical body, and therefore, even if the direction in which the impact force acts is in an unfixed or eccentric state, the impact force can be reliably absorbed.
A nineteenth aspect of the present invention is constructed such that, in the eighteenth aspect, a supporting portion for supporting the spherical body receiver of the receiving pedestal is formed in the shape of a cone whose diameter is reduced in a direction away from the spherical body receiver.
In the shift lever device according to the nineteenth aspect, even if the direction in which the impact force acts is in an unfixed or eccentric state, the spherical body receiver moves along the cone-shaped supporting portion to the center thereof and the impact force can be reliably absorbed accordingly.